engine block head small hairline leak (help please info)

cyberpunx

Well-Known Member
Joined
28 Oct 2007
Messages
134
Location
lanarkshire
Visit site
hi all i am looking for some help anyone know if there is some sort of sealant you can get for very very small hair line crack leaking water from the engine.? it would have to be for obvious heat . (on engine) i have heard you can buy ones you run through an engine i dont think this would suit a marine engine would it not just run in and out the back of boat.?
i am looking for something i can smaer over the small bit about 3 mm long max. but it does drip drip when engine is running. it is the water thats drawn in as i tryed it . YUK. anyway anyone have some idea of maybe something i coould pick up easily from say halfords or chandlers etc.
im at wits end.
also this week well today i brought out my outboard and my cr 250 motocrosser both of them have seals on the carb jiggered strange i think maybe it's the shed heat thats playing havoc with them when i put both of them away they were both fine. ??? help im going daft everything i touch turns to broken aghhghhhhhhh!!!!!!!!!!!!!!!
when i usually have the midas touch.
so any theories about how the carb are leaking they are kept in a small garden shed which does get hot on summer days. the bikes been lying about 5 month and the O/B for only 3 weeks. was fine last timer it was out.


sealant well im sure that should be easy enough once i get put onto some heat resistant sealant.
with your guys help.
cheers john
 
Re: engine block head small hairline leak

Not sure if the leak is in the cylinder head or the block but the only possible cure is to open the crack up by grinding and then weld. if it continues into the head to block interface theres not much hope. Have you checked the oil to see if any water is getting in there?
 
You haven't mentioned the make or model of the engine which might produce more assistance. The whereabouts of the crack is important also.

My experience is that these 'temporary' leak repairers can last for years. Ce-lit which is little more than ground up linseed is cheap and succesful. You could recirculate the water in a bucket until the leak takes up but if you've got a crack, what was the cause?
 
[ QUOTE ]
You haven't mentioned the make or model of the engine

[/ QUOTE ] Everyone knows its a Volvo Penta AQ 105/100
Poor bloke's been working his nuts off long enough.

But reckon I'd try a radiator leak sealer. Warm it up, and recirculate the coolant as you suggest. Nothing to lose and even if it does not hold forever theres not a gushing leak.
 
Speaking from experience of a small corrosion crack across a cylinder block on a volvo MD7 try halfords exhaust manifold repair kit. It contains a filler supposed to withstand very high heat.

Against the reasonable opinion on the forum that the repair would only last 5 minutes in fact it lasted 3 years. Pity I wasn't more optimistic as I sold the boat cheaply on the basis the engine would have to be replaced, but it lasted the whole 3 years of the next owner before failing just after he sold it on !
 
as mentioned yes volvo aq105/100 the line was in sight all electrics done all painting / anti fouling done. engine done check. all my spare time taken check , new mooring bought and layed done arrnage new interior foam upholstry done. then went to change oil again and noticed a small crack along from the volvo sign on the main block on the core plug lip above the oil filter tiny wee thing.
anyway im gutted. ive put my heart and soul into this. and now its more trouble. i am getting to the scunnered mode. but always go back . is this a step too far.
cheers to all who gave time and effort into this project with me. ive came long and far from working out how to raise it from the ocean floor. with floats at high tide.
anyway cheers again thanks for info taken on board as usual. i'll ponder it everything else is done as well i was right there thought it was going onto mooring next weekend. but thats what thought done pee'd the bed and blamed the blankets.
cheers john.
plus im skint now the time ive took off work now means ££ is done so back to work first then think about the next step.
im now in 2 minds what to do.?
 
Jb Weld will do the job. Ensure the crack is clean and dry and rust free. Smear a glob of the mixture on the job and apply some heat from a hot air gun for a few seconds. This will make the mixture more "runny", smear it in further with a small spatula while its fluid and allow to set.
 
Top